Using a passive coordinate measurement arm for motion tracking of a rigid endoscope for augmented-reality image-guided surgery.

Background: One of the main sources of error in commercial surgical navigation systems is the tracking of surgical tools. Mainstream systems typically use optical or electromagnetic tracking technologies, which exhibit accuracies of the order of 1 mm. The objective of this study was to introduce a lightweight high-precision passive coordinate measurement arm into an augmented reality-based surgical navigation system to track a rigid endoscope.

Determination of large bowel length and loop complexity in patients with acromegaly undergoing screening colonoscopy.

Background: Patients with acromegaly are at moderately increased risk of developing colorectal cancer and may be considered for screening colonoscopy. In turn, large bowel dimensions may be increased in these patients, factors that predict for increased risk of serious complications such as perforation.

Objective: To evaluate this risk potential, we measured large bowel length and loop complexity using magnetic endoscopic imaging (MEI).